Prototyping... Anyone have experience with Pad2Pad?

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I searched.    The only references to "Pad2Pad" I could find were made by samwisekoi.  I guess he has used them a few times for projects.  I'd be interested to hear some opinions if anyone else has used them.

The reason I ask is... (STORY TIME) I have this Varmilo switch tester from a recent Massdrop.


https://www.massdrop.com/buy/varmilo-switch-tester (login required)

Yes, that's Comic Sans.

Anyway, the thing comes with a very simple PCB.  I guess Varmilo included it as a nod to the keyboard/modding community.  You can wire it up to a low voltage source and drop some LEDs in it.  The thing is, it's probably the crappiest PCB I've ever owned.  Several pins refuse to take solder (I guess they aren't metal?) and I managed to burn the board a little trying to bend it to my will.  Also the negative pad just came right off the board while I was soldering it...  Major disappointment.  You can see a photo of my hackjob here: http://i.imgur.com/IK5abfm.jpg

So after butchering it  I naively thought, hey, I know almost nothing about electronics.  I could make a better PCB than that!    And popped over to Google to begin my journey.

A week later I had this:



Pad2Pad's software made it easier than I imagined.  Keeping in mind my caveman-level grasp of electronics, what have I done wrong here?  I have a feeling this would work and Pad2Pad would happily print it for me, but if there's a better way I'd like to know before I spend money on it.

• That's a Micro USB B connector (Molex 105017-0001) at the top.  Pad2Pad didn't have ANY Micro USB connectors in their library, but they were nice enough to draw one and email it to me.  I've only done a few basic measurements on it.  I assume it's correct...
• Do I even need 9 resistors?  The Varmilo board comes with a single SMD resistor marked 152.  I understand that means 1500 ohms.  It seemed like overkill to me, but I know nothing, John Snow.
• Is it stupid to break out the USB pins (B1 thru B5)?  I thought it would be cool to have them if I wanted to add something else to it later.  I'm only actually using VCC and GND.

This board isn't supposed to DO anything except light up, look pretty, and use a convenient USB cable.  I realize that's a lot of effort for putting lights on a switch tester, but it's a testament to how frustrated I was by the stock board.  Any feedback, even negative, is greatly appreciated.

Thanks for looking.

[engicoder]

That's a Micro USB B connector (Molex 105017-0001) at the top.  Pad2Pad didn't have ANY Micro USB connectors in their library, but they were nice enough to draw one and email it to me.  I've only done a few basic measurements on it.  I assume it's correct...

Looks about right.

Do I even need 9 resistors?  The Varmilo board comes with a single SMD resistor marked 152.  I understand that means 1500 ohms.  It seemed like overkill to me, but I know nothing, John Snow.

No you don't *need* 9 resistors, but its the better way to do it. The problem with a single resistor is that the led's may draw current unevenly due to slight differences in their properties when they were manufactured. This would lead to a difference in brightness.

Is it stupid to break out the USB pins (B1 thru B5)?  I thought it would be cool to have them if I wanted to add something else to it later.  I'm only actually using VCC and GND.
or looking.

I'm not sure what you would use them for, but they do no harm and someday you may wish you had.

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Nice.  Thanks Engi. 

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The resistor footprint I have is SMT 1206.  Do these resistors look OK for 20mA LEDs @ 3.0-3.2Vf?

http://www.mouser.com/ProductDetail/Panasonic/ERJ-P08F1500V/?qs=sGAEpiMZZMvdGkrng054tzSGWtpoOZZIvjFeKqMvGts%3d

[engicoder]

The resistor footprint I have is SMT 1206.  Do these resistors look OK for 20mA LEDs @ 3.0-3.2Vf?

http://www.mouser.com/ProductDetail/Panasonic/ERJ-P08F1500V/?qs=sGAEpiMZZMvdGkrng054tzSGWtpoOZZIvjFeKqMvGts%3d

5.0-3.0/150 = 0.1333 or about 13 mA
5.0-3.2/150 = 0.12 or about 12 mA
Both are fine for a 20mA LED.

9 * 13 = 117ma - If you push every switch at once 
This may be a problem with some hubs that won't give you more than the 100mA the USB 2.0 spec allows for devices not requesting more. Today I think this is a rare occurrence, so you should be ok. If you want to be 100% sure go with a 180 Ohm which will still give you 11mA

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I'd only ever be plugging directly into a PC USB port, which should be good for up to 500mA right?  I don't think I've seen a USB hub in ages.